Shuttle tension device.



J. E. THAYBR. SHUTTLE TENSION DEVICE.

APPLIOATION FILED DBO. 29, 1906.

974,309; Patented Nov.1,1,910.`

lngsseg: Inventar.'

l j ATQ all whom 'it may concern:

UNITED STATES PATENT OFFICE.

JOSEPH E. TH'AYER, 0F EAST BRIDG-EWATER, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY COMPANY, OF PATERSON, NEW JERSEY, .A CORPORATION F NEW JERSEY.

SHUTTLE TENSION DEVICE.

- Patented Nov. 1, 1910.

Application led December29, 1906. Serial No. 349,980.

Bevit known that I, J osEPH E. THAYER, aa citizen of the United States, residing at East Bridgewater, in the county of Plymouth and State of Massachusetts, have invented certain new and useful Improvements n Shuttle Tension Devices; and I do hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the Same.

threaded into the spring and engaging the body of the thread case of the shuttle. As the space available for these parts is small the screw is very small and is easily broken or worn out, and a further difliculty is encountered in the constant tendency of the A 4screw to turn and release the tension, necessitatin frequent readjustment by the operator o thesewing machine and causing uneven work. r

In the present invention the use of ad- ,jpsting screws or other small or breakable j parts 1s dispensed with, and the device is so constructed that after being adjusted no accidental change is possible, since the parts are locked in place by their position in the machine, and must be removed from the machine in order to be relatively moved.

. Other novel and valuable features of the invention will be pointed out in connection with the description of the illustrated embodiment thereof.

. In the drawings Figure 1 is a perspective view of a'portion of a shuttle embodying the resent invention; Fig. 2 is a plan view,

-part y in section; and Fig. 3 is a perspective view of the tension device detached.

The invention is shown as embodied in a shuttle of a well-known rotary or oscillatory type, and only the thread case of the shuttle 1s shown. The thread case comprises a circular body 1 provided with a bobbin spindle 2 and a thread-delivery nose 3. The body of the case is provided, in the usual manner, with a Wide peripheral reception of the tension, evice. The tenslon device comprises a thread-engaging member 5 and a tension-adjusting member 6 located in the groove 4. and consisting of fiat strips of resilient metal curved to the form of the thread case, and each extending slightly more than half way around the thread case so as to be sprun into place roove 4 for the and retain itself in position agalnst the bottom of the groove. The thread-engraving member 5 has a reduced extremity 7 which engages the thread and presses it against a thread supporting surfate on the thread case, as shown in Fig. l, and is, in the present instance, resilient in itself so as to bear beveled upper surface l0 of the thread-engaging member, and increases the pressure of the latter against the thread.

The opposite extremities of the members 5 and 6 are provided with teeth 1l engaging each other and 'fixin the members in relative longitudinal position, and the member 5 is provided with a pin l2 entering a hole in the wall of the thread case to prevent displacement of the tension device in the groove. To adjust the tension it is necessary only to spring the toothed end of one of the tension memLers out of the groove, slide the member 6 the necessary distance in the groove, and then cause the toothed ends again to engage to lock the parts in adjusted position. In its adjusting movement the member 6 moves longitudinally about the periphery of the thread case in a direction at right angles to the direction of the pressure exerted on the thread. In this manner the extremity 9 of the member 6 is caused to engage a higher vao or lower point on the -inclined surface 10, so

as tobear with more or less pressure thereagainst. After the thread case is inserted .in its recess intheshuttle body, ther-,ttoothed l5 ends of the spring members cann'dt become disengaged, and the device `is positively retained at the proper adjustment.

The devicev comprises only two parts, which are not liablev to break or wear out,

and it can be inserted in shuttles as at present constructed without alteration thereof, in place-of the ordinary tension device above described.'

The invention is applicable to shuttles and 1'5 sewing machines of various kinds, and is not presslng it against the thread, the members eing relatively adjustable at substantially right an lesto the direction of pressure to change-t eir point of engagement and vary the tension, substanti ally as described.

2. A shuttle tension for sewing machines, having, in/ combination, with a circular thread case provided with. a peripheral groove, a thread engaging member, and a tension adjusting member mounted in said groove and arranged to engage the thread engaging member, said ytension adjusting member being longitudinally adjustable in 'said-groove, substantially as described.

' `3. A shuttle tension forsewing machines,

40 having, :in combination, with a circular thread case provided with a peripheral grQove, a thread engaging member and a tension adjusting' member engaging the thread engaging member, said members being mounted in the groove so as to be capable-of a relative longitudinal. adjustment therein to vary the tension, Asubstantially as described.

4. A shuttle tension for sewing machines having, in combination, a thread supporting surface, a tension spring engaging the thread, and a tension-adjusting spring engaging the tension spring, one of said springs being beveled at their point of engagement and the springg being adjustable longitudinally with respect to each other to vary the tension,sub stantiallyf as described.

5. A' shuttle tension for sewing machines,

having, 1n combination, with a circular thread case, a thread engaging member, a

tension adjusting, member extending about the periphery of the thread case and arranged to engage the thread engaging member, said tension adjusting member belng ading adjustably-interlocking ends4 to permitv of their relative longitudinal adjustment to vary the tension, substantiallyas described.

7. A shuttle tension for sewing machines having, in combination with a circular thread case provided with a peripheral groove, a thread-engaging member curved to conform to the periphery and removably inserted in the oove, said member extending more than alf way around the thread case to retain itself in said groove, substantially as described.

8. A shuttle tension for sewing machines having, in combination with a circular thread holder rovided with a peripheral groove, a threa -engaging member and a tension adjusting member engaging the thread-engaging member, said members being curved to conformto the periphery of the thread case and removably inserted in the groove, being retained in place by the Walls of the recess in which the thread holder is located, substantially as described.

9. A shuttle tension for sewing machines having, in 'combination With acircular thread holder provided with a peripheral. groove, a thread-engaging member provided with a beveled surface on its thread-engaging portion, and a tension-adjusting member engaging said beveled surface, the members being curved to conform to the periphery of the thread case and being removably inserted in the oove, one of the members being longitu inally adjustable in the groove to vary the 'tension and the other being provided With means for preventing longitudinal movement, substantially as described.

10. A shuttle tension for sewing machines,

having, in combination, with a circular thread case, a thread engaging member eX- tending about the periphery of the thread case and a tension adjusting member also extending about the periphery of thethread case and yarranged to bear upon the thread engagin member, .said members being relatively a justable about the periphery of the thread case to vary the tension, substantially as described.

ll. A shuttle tension device for sewing machines, having, in combination, with a cylindricall thread case having a peripheral' groove, a thread engaging member mounted 1n the groove, and a tension adjusting mem-` ber mounted in the groove and provided i u cam surface to bear on the thread enga f- 1C with u' cum sl'uface arranged to bear on the ing member, and means for lockin(r the te11- thi-end engaging member.l sion adjusting 'member in ndjuste position. 1Q. A shuttle tension device for sewin In testimony whereof I affix my signature, in presence of two witnesses.

JOSEPH F. THAYER.

machines, having, in combination with a cylindrical thread case having a peripheral groove, n ythread engaigingmember mounted in the groove, n tension adjusting member mounted in the groove and provided with Witnesses v FARN inw F. DoRsnY, ALFRED H. HILDRETH. 

